1. Technical Field
Various embodiments of the present disclosure may generally relate to memory controllers, memory systems, and methods relating to wear-leveling.
2. Related Art
Nonvolatile memory devices may be employed in digital electronic systems that operate at a high speed for wireless communication or other applications. The nonvolatile memory devices such as resistive random access memory (ReRAM) devices and phase change random access memory (PCRAM) devices have limited write endurance. The write endurance may be defined as the number of program/erasure operations that can be applied to memory blocks until the reliability of storage media including the memory blocks is lost. The write endurance may be calculated by evaluating how many times the memory blocks can be entirely programmed and erased.
Wear-leveling (also written as wear levelling) is a technique used for prolonging the write endurance of the storage media. According to the wear-leveling technique, the write operations may be performed evenly across memory cells in the storage medium to reduce the number of times that specific memory cells are repeatedly programed. As a result, all of the memory cells may be equally used during the write operations. In general, the wear-leveling operation may be executed by a memory controller. For example, if a write command is applied to the storage medium, the memory controller may execute an appropriate mapping operation between a logical address and a physical address of selected memory cells and may change the physical address of the selected memory cells into another physical address to newly select memory cells when the number of the overwrites of the selected memory cell is greater than a predetermined number of times.